Institutional HoldersBeta

Who holds a company, from every 13F filed for the quarter, one row per filer exactly as filed, against the latest share count the company reported.

Mayville Engineering Company, Inc.

CIK 0001766368MEC· quarter ending 2026-06-30

Shares outstanding

25,500,331

as of 2026-07-31 · 10-Q cover page, filed 2026-08-05

Held by 13F filers

21,628,823

84.8% of shares outstanding

Holders

155

+31 vs 2026-03-31 · 53 new, 22 exited

Value

$807.5M

shares +50.2% vs prior quarter

Share classes (cover page of the 10-Q filed 2026-08-05, as of 2026-07-31)

Class	Listed	Shares outstanding	Held by 13F filers	% of class	Holders	CUSIP
Common stock	MEC · NYSE	25,500,331	21,628,823	84.8%	155	578605107

Each class is compared with its own share count; classes are not added together. A class that is not exchange-listed cannot be held by 13F filers.

Securities (CUSIPs held in 13F this quarter)

tick to combine

Count	CUSIP	Class (as filers write it)	Holders	Shares held	Class shares	% of class	Value	Options	Mapped via
	578605107	COM	155	21,628,823	25,500,331	84.8%	$807.5M	6 call / 4 put	13DG	holders →

Totals combine the ticked CUSIPs and update as you tick: common-stock classes by default; preferreds, notes, warrants and depositary shares are listed but not counted. "holders →" shows a single CUSIP on its own. Bonds are held as a principal amount, not shares. Options positions are never counted as holdings.

Top holders (155 of 155 · 578605107)

change vs 2026-03-31

#	Filer	Shares	% of class	Value	Change
1	Portolan Capital Management, LLC	1,299,256	5.10%	$48.7M	+478,120 (+58.2%)
2	FMR LLC	1,280,170	5.02%	$48.0M	+1,275,909 (+29943.9%)
3	BlackRock, Inc.	1,183,443	4.64%	$44.3M	+301,589 (+34.2%)
4	Allspring Global Investments Holdings, LLC	1,072,916	4.21%	$37.8M	-927,434 (-46.4%)
5	Driehaus Capital Management LLC	846,354	3.32%	$31.7M	NEW
6	SUMMIT PARTNERS PUBLIC ASSET MANAGEMENT, LLC	800,000	3.14%	$30.0M	NEW
7	DIMENSIONAL FUND ADVISORS LP	782,276	3.07%	$29.3M	-143,940 (-15.5%)
8	ROYCE & ASSOCIATES LP	752,083	2.95%	$28.2M	+1,082 (+0.1%)
9	VANGUARD CAPITAL MANAGEMENT LLC	743,621	2.92%	$27.9M	+148,683 (+25.0%)
10	First Eagle Investment Management, LLC	739,150	2.90%	$27.7M	+335,075 (+82.9%)
11	Boston Partners	696,429	2.73%	$25.8M	+463,792 (+199.4%)
12	Jupiter Topco LLC	575,278	2.26%	$21.5M	NEW
13	BLAIR WILLIAM & CO/IL	546,714	2.14%	$20.5M	-18,586 (-3.3%)
14	WELLINGTON MANAGEMENT GROUP LLP	477,583	1.87%	$17.9M	NEW
15	EVR Research LP	441,908	1.73%	$16.6M	-178,092 (-28.7%)
16	GEODE CAPITAL MANAGEMENT, LLC	374,578	1.47%	$14.0M	+38,743 (+11.5%)
17	JANE STREET GROUP, LLC	356,151	1.40%	$13.3M	NEW
18	JPMORGAN CHASE & CO	347,224	1.36%	$13.0M	+341,743 (+6235.0%)
19	KENNEDY CAPITAL MANAGEMENT LLC	336,377	1.32%	$12.6M	+229,586 (+215.0%)
20	Ophir Asset Management Pty Ltd	326,699	1.28%	$12.2M	NEW
21	Granahan Investment Management, LLC	324,108	1.27%	$12.1M	-63,362 (-16.4%)
22	SILVERCREST ASSET MANAGEMENT GROUP LLC	313,943	1.23%	$11.8M	+44,262 (+16.4%)
23	STATE STREET CORP	291,168	1.14%	$10.9M	+5,318 (+1.9%)
24	Nuveen, LLC	281,914	1.11%	$10.6M	+234,496 (+494.5%)
25	BANK OF AMERICA CORP /DE/	276,317	1.08%	$10.4M	+92,718 (+50.5%)
26	MILLENNIUM MANAGEMENT LLC	253,677	0.99%	$9.5M	-127,295 (-33.4%)
27	JB CAPITAL PARTNERS LP	250,512	0.98%	$9.4M	—
28	Squarepoint Ops LLC	238,766	0.94%	$8.9M	+128,197 (+115.9%)
29	CONGRUENCE CAPITAL, LLC	235,580	0.92%	$8.8M	+1,105 (+0.5%)
30	BRIDGEWAY CAPITAL MANAGEMENT, LLC	200,980	0.79%	$7.5M	-21,723 (-9.8%)
31	TWO SIGMA INVESTMENTS, LP	198,912	0.78%	$7.5M	+164,204 (+473.1%)
32	CITADEL ADVISORS LLC	198,712	0.78%	$7.4M	+141,926 (+249.9%)
33	AWM Investment Company, Inc.	180,000	0.71%	$6.7M	NEW
34	OSTERWEIS CAPITAL MANAGEMENT INC	174,600	0.68%	$6.5M	NEW
35	TUDOR INVESTMENT CORP ET AL	169,848	0.67%	$6.4M	NEW
36	ANCHOR CAPITAL ADVISORS LLC	161,768	0.63%	$6.1M	+80,326 (+98.6%)
37	LORD, ABBETT & CO. LLC	152,175	0.60%	$5.7M	NEW
38	Wealthspire Advisors, LLC	141,607	0.56%	$5.3M	—
39	Pillsbury Lake Capital LLC	136,746	0.54%	$5.1M	NEW
40	Informed Momentum Co LLC	129,182	0.51%	$4.8M	NEW
41	Russell Investments Group, Ltd.	125,513	0.49%	$4.7M	-12,702 (-9.2%)
42	SEI INVESTMENTS CO	118,607	0.47%	$4.4M	-4,271 (-3.5%)
43	Empowered Funds, LLC	116,570	0.46%	$4.4M	-6,723 (-5.5%)
44	NORTHERN TRUST CORP	114,995	0.45%	$4.3M	+14,611 (+14.6%)
45	BNP PARIBAS FINANCIAL MARKETS	112,455	0.44%	$4.2M	+109,657 (+3919.1%)
46	NEEDHAM INVESTMENT MANAGEMENT LLC	110,000	0.43%	$4.1M	+90,000 (+450.0%)
47	HUNTER ASSOCIATES INVESTMENT MANAGEMENT LLC	107,528	0.42%	$4.0M	NEW
48	Trexquant Investment LP	100,517	0.39%	$3.8M	NEW
49	MORGAN STANLEY	100,159	0.39%	$3.8M	+76,325 (+320.2%)
50	VANGUARD FIDUCIARY TRUST CO	98,709	0.39%	$3.7M	+7,665 (+8.4%)
51	VANGUARD PORTFOLIO MANAGEMENT LLC	98,263	0.39%	$3.7M	+22,360 (+29.5%)
52	Walleye Capital LLC	93,444	0.37%	$3.5M	NEW
53	Qube Research & Technologies Ltd	87,129	0.34%	$3.3M	NEW
54	SUSQUEHANNA INTERNATIONAL GROUP, LLP	85,462	0.34%	$3.2M	NEW
55	UBS Group AG	82,662	0.32%	$3.1M	-33,909 (-29.1%)
56	Invesco Ltd.	75,331	0.30%	$2.8M	+48,303 (+178.7%)
57	FORMULA GROWTH LTD	75,000	0.29%	$2.8M	-25,000 (-25.0%)
58	TOCQUEVILLE ASSET MANAGEMENT L.P.	71,100	0.28%	$2.7M	—
59	Panoramic Capital, LLC	70,000	0.27%	$2.6M	-70,000 (-50.0%)
60	XTX Topco Ltd	65,604	0.26%	$2.5M	+24,126 (+58.2%)
61	POLEN CAPITAL MANAGEMENT LLC	61,827	0.24%	$2.3M	NEW
62	Essential Investment Partners LLC	58,886	0.23%	$2.2M	+19,247 (+48.6%)
63	CITIGROUP INC	52,620	0.21%	$2.0M	+50,983 (+3114.4%)
64	GOLDMAN SACHS GROUP INC	51,990	0.20%	$1.9M	-12,918 (-19.9%)
65	AMERICAN CENTURY COMPANIES INC	48,211	0.19%	$1.8M	-173,462 (-78.3%)
66	Balyasny Asset Management L.P.	47,052	0.18%	$1.8M	NEW
67	CHARLES SCHWAB INVESTMENT MANAGEMENT INC	45,861	0.18%	$1.7M	+5,763 (+14.4%)
68	SummerHaven Investment Management, LLC	45,325	0.18%	$1.7M	—
69	Bank of New York Mellon Corp	44,873	0.18%	$1.7M	+6,022 (+15.5%)
70	GatePass Capital, LLC	40,000	0.16%	$1.5M	NEW
71	OSAIC HOLDINGS, INC.	39,614	0.16%	$1.5M	-59,490 (-60.0%)
72	SHEETS SMITH WEALTH MANAGEMENT	37,897	0.15%	$1.4M	-1,078 (-2.8%)
73	Diametric Capital, LP	35,727	0.14%	$1.3M	NEW
74	Aquatic Capital Management LLC	31,731	0.12%	$1.2M	+22,830 (+256.5%)
75	Janney Montgomery Scott LLC	31,304	0.12%	$1.2M	-1 (-0.0%)
76	CenterBook Partners LP	30,992	0.12%	$1.2M	-89,311 (-74.2%)
77	BOOTHBAY FUND MANAGEMENT, LLC	30,584	0.12%	$1.1M	NEW
78	North Star Investment Management Corp.	30,000	0.12%	$1.1M	—
79	KORNITZER CAPITAL MANAGEMENT INC /KS	29,587	0.12%	$1.1M	NEW
80	HARBOR CAPITAL ADVISORS, INC.	28,625	0.11%	$1.1M	+20,840 (+267.7%)
81	RENAISSANCE TECHNOLOGIES LLC	28,000	0.11%	$1.0M	-34,900 (-55.5%)
82	Divisadero Street Capital Management, LP	27,482	0.11%	$1.0M	NEW
83	Quadrature Capital Ltd	26,477	0.10%	$992K	NEW
84	Johnson Financial Group, Inc.	26,000	0.10%	$974K	+9,525 (+57.8%)
85	PRELUDE CAPITAL MANAGEMENT, LLC	23,969	0.09%	$898K	NEW
86	LPL Financial LLC	22,172	0.09%	$831K	+401 (+1.8%)
87	O'SHAUGHNESSY ASSET MANAGEMENT, LLC	21,785	0.09%	$816K	-4,585 (-17.4%)
88	HRT FINANCIAL LP	21,568	0.08%	$807K	NEW
89	WELLS FARGO & COMPANY/MN	20,300	0.08%	$760K	+7,731 (+61.5%)
90	RHUMBLINE ADVISERS	20,001	0.08%	$749K	+1,801 (+9.9%)
91	ENVESTNET ASSET MANAGEMENT INC	18,920	0.07%	$709K	-1,381 (-6.8%)
92	AQR CAPITAL MANAGEMENT LLC	18,224	0.07%	$683K	-2,159 (-10.6%)
93	STATE OF WISCONSIN INVESTMENT BOARD	18,171	0.07%	$681K	-14,091 (-43.7%)
94	WESBANCO BANK INC	18,000	0.07%	$674K	NEW
95	DEUTSCHE BANK AG\	14,278	0.06%	$535K	+4,041 (+39.5%)
96	Caption Management, LLC	14,092	0.06%	$528K	NEW
97	WEALTH ENHANCEMENT ADVISORY SERVICES, LLC	13,946	0.05%	$470K	NEW
98	FRANKLIN RESOURCES INC	12,816	0.05%	$480K	-712 (-5.3%)
99	Numerai GP LLC	12,410	0.05%	$465K	-27,345 (-68.8%)
100	Creative Planning	12,159	0.05%	$455K	NEW
101	PRICE T ROWE ASSOCIATES INC /MD/	12,026	0.05%	$451K	NEW
102	US BANCORP \DE\	11,385	0.04%	$426K	+11,374 (+103400.0%)
103	EntryPoint Capital, LLC	10,793	0.04%	$404K	NEW
104	Worth Venture Partners, LLC	10,641	0.04%	$399K	-4,469 (-29.6%)
105	BARCLAYS PLC	10,197	0.04%	$382K	-8,831 (-46.4%)
106	Heck Capital Advisors, LLC	10,072	0.04%	$377K	-1,422 (-12.4%)
107	DELTA CAPITAL MANAGEMENT LLC	9,920	0.04%	$372K	NEW
108	Schonfeld Strategic Advisors LLC	9,606	0.04%	$360K	NEW
109	Centiva Capital, LP	9,504	0.04%	$356K	NEW
110	MetLife Investment Management, LLC	8,648	0.03%	$324K	+690 (+8.7%)
111	Vanguard Global Advisers, LLC	8,118	0.03%	$304K	+2,182 (+36.8%)
112	HARBOUR INVESTMENTS, INC.	7,700	0.03%	$288K	—
113	Avior Wealth Management, LLC	7,519	0.03%	$282K	-7,400 (-49.6%)
114	RAYMOND JAMES FINANCIAL INC	7,490	0.03%	$281K	NEW
115	Quantbot Technologies LP	7,027	0.03%	$263K	NEW
116	Connor, Clark & Lunn Investment Management Ltd.	6,918	0.03%	$259K	NEW
117	Calamos Advisors LLC	6,883	0.03%	$258K	NEW
118	GSA CAPITAL PARTNERS LLP	6,814	0.03%	$255K	NEW
119	MIRAE ASSET GLOBAL ETFS HOLDINGS Ltd.	6,743	0.03%	$253K	+502 (+8.0%)
120	Engineers Gate Manager LP	5,683	0.02%	$213K	NEW
121	OCCUDO QUANTITATIVE STRATEGIES LP	5,634	0.02%	$211K	NEW
122	Brevan Howard Capital Management LP	5,581	0.02%	$209K	-6,442 (-53.6%)
123	NEW YORK STATE COMMON RETIREMENT FUND	5,395	0.02%	$202K	—
124	Police & Firemen's Retirement System of New Jersey	4,651	0.02%	$174K	—
125	JONES FINANCIAL COMPANIES LLLP	4,560	0.02%	$169K	-1,621 (-26.2%)
126	State of Alaska, Department of Revenue	3,903	0.02%	$146K	—
127	Persistent Asset Partners Ltd	2,147	0.01%	$80K	NEW
128	Parkside Financial Bank & Trust	1,665	0.01%	$62K	+1,630 (+4657.1%)
129	SIMPLEX TRADING, LLC	1,529	0.01%	$57K	NEW
130	Legal & General Group Plc	1,420	0.01%	$53K	+160 (+12.7%)
131	Ameritas Investment Partners, Inc.	1,329	0.01%	$50K	-125 (-8.6%)
132	Avion Wealth	1,000	0.00%	$37K	—
133	Caitong International Asset Management Co., Ltd	943	0.00%	$35K	NEW
134	Arax Advisory Partners	709	0.00%	$27K	NEW
135	Tower Research Capital LLC (TRC)	636	0.00%	$24K	-645 (-50.4%)
136	ROYAL BANK OF CANADA	561	0.00%	$21K	-2,886 (-83.7%)
137	BARD ASSOCIATES INC	500	0.00%	$19K	NEW
138	Sterling Capital Management LLC	295	0.00%	$11K	-106 (-26.4%)
139	Rockefeller Capital Management L.P.	276	0.00%	$10K	—
140	UBS AM, a distinct business unit of UBS ASSET MANAGEMENT AMERICAS LLC	229	0.00%	$9K	—
141	CALIFORNIA STATE TEACHERS RETIREMENT SYSTEM	184	0.00%	$7K	-524 (-74.0%)
142	GAMMA Investing LLC	174	0.00%	$7K	—
143	Clearstead Advisors, LLC	131	0.00%	$5K	NEW
144	FIFTH THIRD BANCORP	118	0.00%	$4K	—
145	Allworth Financial LP	66	0.00%	$2K	+8 (+13.8%)
146	Farther Finance Advisors, LLC	48	0.00%	$2K	+34 (+242.9%)
147	Quarry LP	44	0.00%	$2K	NEW
148	Bare Financial Services, Inc	37	0.00%	$1K	—
149	EverSource Wealth Advisors, LLC	27	0.00%	$1K	+2 (+8.0%)
150	NISA INVESTMENT ADVISORS, LLC	26	0.00%	$974	—
151	PNC Financial Services Group, Inc.	20	0.00%	$749	—
152	Bruce G. Allen Investments, LLC	18	0.00%	$674	NEW
153	Essential Partners LLC	14	0.00%	$524	—
154	SIGNATUREFD, LLC	13	0.00%	$487	NEW
155	NATIONAL BANK OF CANADA /FI/	4	0.00%	$149	NEW

Exited since 2026-03-31 (22 filers; largest 22 shown)

AMERIPRISE FINANCIAL INC	−351,790
Roubaix Capital, LLC	−210,657
ARROWSTREET CAPITAL, LIMITED PARTNERSHIP	−185,261
Integrated Quantitative Investments LLC	−50,659
HighTower Advisors, LLC	−44,587
JOURNEY STRATEGIC WEALTH LLC	−44,206
PANAGORA ASSET MANAGEMENT INC	−36,765
Legato Capital Management LLC	−35,698
Ancora Advisors LLC	−32,133
SummitTX Capital, L.P.	−18,696
Gradient Investments LLC	−17,104
ALLIANCEBERNSTEIN L.P.	−12,810
MIRABELLA FINANCIAL SERVICES LLP	−12,430
CWM, LLC	−922
MAI Capital Management	−414
Optiver Holding B.V.	−124
Advisory Services Network, LLC	−115
Annis Gardner Whiting Capital Advisors, LLC	−80
BAYBAN	−43
Vermillion Wealth Management, Inc.	−30
True Wealth Design, LLC	−9
Root Financial Partners, LLC	−5

Large holders from 13D/13G (latest per reporting person, last 2 years)

Filed when a holder crosses 5% or changes materially, so often more current than the quarter-end 13F. Percentages are the filer's own, against the share count they used.

Reporting person	Form	Filed	Event	Shares	% of class
Abigail P. Johnson	SCHEDULE 13G	2026-08-06	2026-06-30	1,280,170.12	5%
FMR LLC	SCHEDULE 13G	2026-08-06	2026-06-30	1,280,170.12	5%
Allspring Global Investments Holdings, LLC	SCHEDULE 13G/A	2026-07-08	2026-06-30	1,072,916	4.2%
George McCabe	SCHEDULE 13G	2026-05-28	2026-05-20	1,465,004	5.92%
Portolan Capital Management, LLC	SCHEDULE 13G	2026-05-28	2026-05-20	1,465,004	5.92%
Hilve Holdings Ltd	SCHEDULE 13G/A	2026-02-13	2025-10-27	995,756	4.9%
Mikhail Stiskin	SCHEDULE 13G/A	2026-02-13	2025-10-27	995,756	4.9%

Source: SEC Form 13F-HR information tables for the quarter ending 2026-06-30 (filed within 45 days of quarter end; amendments applied; values normalised to dollars), the share count from the company's latest 10-K/10-Q XBRL cover page, and Schedule 13D/13G filings. Each row is a legal 13F filer as filed — related entities (e.g. Vanguard's advisers) are not merged. Retail brokerage accounts are not reported on 13F, so the remainder is mostly retail and insiders.